And here's why Samsung and Nanosys are talking about a hybrid OLED/QLED.

Looks like they've got a ways to go on blue qdot lifetime when used as electroluminescent QLED. This is a good read.

Quote:

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Article Published: 15 February 2019

On the degradation mechanisms of quantum-dot light-emitting diodes
Song Chen, Weiran Cao, Taili Liu, Sai-Wing Tsang, Yixing Yang, Xiaolin Yan & Lei Qian
Nature Communicationsvolume 10, Article number: 765 (2019) | Download Citation

Abstract
The operating lifetime of blue quantum-dot light-emitting diodes (QLED) is currently a short slab for this emerging display technology. To pinpoint the origin of device degradation, here we apply multiple techniques to monitor the electric-field distribution and space-charge accumulation across the multilayered structure before and after lifetime tests. Evident by charge-modulated electro-absorption and capacitance-voltage characteristics, the excited electrons in blue quantum dots (QD) are prone to cross the type II junction between the QD emission layer and the electron-transporting layer (ETL) due to the offset of conduction band minimum, leading to space-charge accumulation and operating-voltage rise in the ETL. Therefore, unlike those very stable red devices, of which the lifetime is primarily limited by the slow degradation of hole-transporting layer, the poor lifetime of blue QLED originates from the fast degradation at the QD-ETL junction. Materials engineering for efficient electron injection is prerequisite for the boost of operating lifetime.

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https://www.nature.com/articles/s41467-019-08749-2